A Windows password cracker based on rainbow tables
Ophcrack is a Windows password cracker based on a time-memory trade-off using rainbow tables. This is a new variant of Hellman's original trade-off, with better performance. It recovers 99.9% of alphanumeric passwords in seconds.
BruteNet is a system of the distributed brute force and distributed calculations built on user extensions capable to solve a great number of problems related to the partition on a lot of machines.With sample extention you can distribute brute md5-hash
Secwatch is an intrusion detection system using log analysis to detect service scan and other brute-force attempts on a server or other computer using system logs and will create temporary firewall rules to block offending IPs
brutesshd is an application written in c/php in order to prevent bruteforce attacks through ssh. Brutesshd uses iptables/pfctl tools to block this type of attacks
NBTView is a 'NetBIOS Swiss Army Knife' written in C, and usable under several UNIX-like systems. NBTView allows you to passively monitor NetBIOS intelligence (users logged in, shares, etc.), run queries against machines, and brute-force share passwords.